For help cleaning an infected computer visit the icode website
http://www.icode.net.au/

The icode website offers information for people with computers that may have been infected with malicious software, to help them remove the malicious software and understand the steps they can take to better protect themselves online in the future.

Velocity Internet also recommends Malwarebytes' Anti-Malware for removal of malware infections.

Get the Free version from http://www.malwarebytes.org/mbam.php